Anastomosis System with Cutting Element

ABSTRACT

A surgical tool for performing anastomosis between a graft vessel and a target vessel may include an anvil; a cutting element connected to the anvil; and an energy source connected to the cutting element, wherein the energy source is configured to deliver energy to the cutting element. A method for performing anastomosis with that tool may include placing an end of the graft vessel against a side of the target vessel; creating an opening in the wall of the target vessel at a first location; inserting an anvil through the opening from outside the wall of the target vessel into the lumen of the target vessel; creating an incision in the wall of the target vessel spaced apart from the first location; and connecting the graft vessel to the target vessel.

This application is a divisional of U.S. patent application Ser. No.10/151,441, filed on May 20, 2002, which in turn is acontinuation-in-part of U.S. patent application Ser. No. 09/363,255,filed on Jul. 28, 1999, now U.S. Pat. No. 6,391,038, each of which isherein incorporated by reference in its entirety.

FIELD OF THE INVENTION

The invention relates to an apparatus and method for performinganastomosis.

BACKGROUND

Anastomosis is a procedure by which two hollow tissue structures arejoined together. More particularly, vascular anastomosis is a procedureby which two blood vessels within a patient are surgically joinedtogether. Vascular anastomosis is performed during treatment of avariety of conditions including coronary artery disease, diseases of thegreat and peripheral vessels, organ transplantation, and trauma. Incoronary artery disease (CAD) an occlusion or stenosis in a coronaryartery interferes with blood flow to the heart muscle. Treatment of CADinvolves the grafting of a vessel in the form of a prosthesis orharvested artery or vein to reroute blood flow around the occlusion andrestore adequate blood flow to the heart muscle. This treatment is knownas coronary artery bypass grafting (CABG).

In the conventional CABG, a large incision is made in the chest and thesternum is sawed in half to allow access to the heart. In addition, aheart-lung machine is used to circulate the patient's blood so that theheart can be stopped and the anastomosis can be performed. In order tominimize the trauma to the patient induced by conventional CABG, lessinvasive techniques have been developed in which the surgery isperformed through small incisions in the patient's chest with the aid ofvisualizing scopes. In both conventional and less invasive CABGprocedures, the surgeon has to suture one end of the graft vessel to thecoronary artery and the other end of the graft vessel to ablood-supplying artery, such as the aorta. The suturing process is atime consuming and difficult procedure requiring a high level ofsurgical skill. In order to perform the suturing of the graft to atarget vessel such as the coronary artery or the blood supplying artery,a surgeon holds the edges of the incision in the target vessel with onehandle and holds a needle in the other hand for suturing, or anassistant may hold the edges of the incision in the target vessel whilea surgeon makes small stitches as close as possible to the edges of theincision. This suturing requires a high degree of precision and is quitetime consuming. In addition, during conventional CABG procedures bloodflow at the anastomosis site is stopped during suturing. This preventsbleeding from the incision site but also prevents blood from reaching aportion of the heart muscle served by the vessel. Further, duringoff-pump CABG procedures a side clamp or other device may be used toisolate a portion of the wall of the aorta to which a graft vessel issutured. The use of a side clamp or similar device can cause emboli todetach from the wall of the aorta and enter the bloodstream, which isundesirable.

Accordingly, it would be desirable to provide a vascular anastomosissystem that allows the tissue at the anastomosis site to be controlledduring suturing or other connection of the graft and target vessels. Itwould also be desirable to provide a vascular anastomosis system thatallows the connection of a graft vessel to a target vessel prior tomaking an incision in the target vessel which allows blood flow betweenthe target vessel and the graft vessel.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an anvil and a plurality of staplesaccording to a first aspect of the present invention.

FIG. 2 is a perspective view of the anvil of FIG. 1 being inserted intoa target vessel.

FIG. 3 is a perspective view of the anvil tenting a wall of a targetvessel for an anastomosis procedure.

FIG. 4 is a perspective view of a graft vessel placed adjacent anexterior of the tented target vessel for the anastomosis procedure.

FIG. 5 is a perspective view of the staples being applied to the graftvessel and the target vessel during an anastomosis procedure.

FIG. 6 is a perspective view of the completed anastomosis according tothe first aspect of the present invention.

FIG. 7 is a perspective view of a staple supported on a staple holdingstrip.

FIG. 8 is a side view of the staple and staple holding strip of FIG. 7when the ends of the staple have been bent by contact with an anvil.

FIG. 9 is a perspective view of an anvil and staple according to anotheraspect of the present invention.

FIGS. 10A and 10B are is a side views of a plurality of staplessupported on two examples of expandable staple holding strips.

FIG. 11 is a perspective view of a portion of an anvil having a movablecutting device.

FIG. 12 is a side view of an anvil having an external cutting device.

FIGS. 12A and 12B are side views of a portion of an anvil and twocutting devices that snap onto the anvil.

FIG. 13 is a side view of a portion of an anvil with an extendablecutting device.

FIG. 14 is a side view of the anvil of FIG. 13 with the cutting deviceextended.

FIG. 15 is a side view of a portion of an anvil with an alternateextendable cutting device.

FIG. 16 is a side view of the anvil of FIG. 15 with the cutting deviceextended.

FIG. 17 is a perspective view of an anvil according to a second aspectof the invention being inserted into a target vessel.

FIG. 18 is a perspective view of the anvil of FIG. 17 positioning insidea target vessel and a clamp being advanced to clamp the wall of thetarget vessel between the anvil and the clamp.

FIG. 19 is a perspective view of a graft vessel being advanced to thetarget vessel with a continuous anastomosis staple while the anastomosissite on the target vessel is controlled by the anvil and clamp.

FIGS. 20-22 are side cross sectional views of the steps of performingthe anastomosis with the continuous anastomosis staple shown in FIG. 19.

FIG. 23 is a perspective view of the completed anastomosis performed asshown in FIGS. 19-22.

FIGS. 24-27 are perspective views of the steps of an alternative anviland clamp system for controlling an anastomosis site and forming anincision through the clamped tissue of the target vessel.

FIG. 28 is a perspective view of a system for controlling a tissue siteand performing anastomosis according to the present invention.

FIG. 29 is a cross sectional view taken along line C-C of FIG. 28,showing a first step of the anastomosis procedure.

FIG. 30 is a cross sectional view taken along line C-C of FIG. 28,showing a second step of the anastomosis procedure.

FIG. 31 is a cross sectional view taken along line C-C of FIG. 28,showing a third step of the anastomosis procedure.

FIG. 32 is a perspective view of an anvil according to another aspect ofthe present invention for use with sutures.

FIG. 33 is a perspective view of the anvil of FIG. 32 positioned withina target vessel and used to locate a plurality of suture at ananastomosis site.

FIG. 34 is a side cutaway view of a first embodiment of an anvil, acutter and a staple holder, where the anvil and staple holder are spacedapart from each other.

FIG. 35 is an end cross-section view of the anvil of FIG. 34.

FIG. 36 is a side cutaway view of a portion of the anvil inserted intothe lumen of a target vessel.

FIG. 37 is a side view of the cutter.

FIG. 38 is a perspective view of the cutter of FIG. 37.

FIG. 39 is a side view of the distal end of a second embodiment of acutter.

FIG. 40 is a side view of the distal end of a third embodiment of acutter.

FIG. 41 is a side view of the distal end of a fourth embodiment of acutter.

FIG. 42 is a side view of a portion of a fifth embodiment of a cutter.

FIG. 43 is a side view of the distal end of a sixth embodiment of acutter.

FIG. 44 is a side cutaway view of the anvil and staple holder of FIG.34, where the cutter is in a first position.

FIG. 45 is a side cutaway view of the anvil and staple holder of FIG.34, where the cutter is in a second position.

FIG. 46 is a side cutaway view of the anvil and staple holder of FIG.34, where the cutter is in a third position.

FIG. 47 is a side cutaway view of the anvil and staple holder of FIG.34, where the cutter is in a fourth position.

FIG. 48 is a side cutaway view of the anvil and staple holder of FIG.34, where the cutter is in a fifth position.

FIG. 49 is a side cutaway view of a second embodiment of an anvil and astaple holder, where the anvil and staple holder are spaced apart fromeach other.

FIG. 50 is a side cutaway view of the anvil and staple holder of FIG.40, where the cutter is in a first position.

FIG. 51 is a side cutaway view of the anvil and staple holder of FIG.40, where the cutter is in a second position.

FIG. 52 is a side cutaway view of the anvil and staple holder of FIG.40, where the cutter is in a third position.

FIG. 53 is a side cutaway view of the anvil and staple holder of FIG.40, where the cutter is in a fourth position.

FIG. 54 is a side cutaway view of the anvil and staple holder of FIG.40, where the cutter is in a fifth position.

The use of the same reference symbols in different figures indicatessimilar or identical items.

DETAILED DESCRIPTION

As shown in FIG. 1, one embodiment of an anvil 10 includes a handle 12and an anvil arm 14 extending from the handle 12. The anvil arm 14 maybe oriented substantially perpendicular to the handle 12, or oriented ata different angle. The anvil arm 14 may be provided with one or morestaple bending features 16 on opposite sides of the anvil arm 14. In theanvil 10 shown in FIG. 1, the staple bending features 16 each include aplurality of recesses 20 which receive the ends of staples 22 and causethe staple ends to bend over. At least one of the staple bendingfeatures 16 may be configured differently or omitted, if desired. Thestaples 22 may be connected to a staple holding strip 24. The staples 22are U-shaped and are arranged in a spaced apart parallel configurationsuch that the staples 22 all lie in a single plane. Alternately, thestaples 22 may be shaped differently, and/or lie in one or moredifferent planes. An exemplary anvil arm 14 has a height and a width ofabout 2 mm or less, advantageously about 1 mm or less, and a length ofabout 2 to 15 mm, advantageously 5 to 12 mm. The length of the anvilwill vary depending on the diameter of the graft vessel selected. Thelength to width ratio of the anvil arm 14 is substantially between 2:1and 15:1. A different length to width ratio may be used, if desired. Asone example, the staples 22 have widths of about 0.2-3 mm.Advantageously, the staples 22 have widths of substantially 2 mm orless. The leg lengths of the staples 22 are substantially 0.2-3 mm.Alternately, other leg lengths may be used.

The anvil arm 14 has a sharp distal end 28 for puncturing the tissue ofa target vessel to insert the anvil arm 14 into the target vessel. Asillustrated in FIG. 2, the anvil arm 14 is inserted into a pressurizedor unpressurized target vessel 30 by puncturing the target vessel withthe distal end 28 of the anvil arm 14. The hole that is formed in thewall of the target vessel 30 by the anvil arm 14 is small enough toprevent significant bleeding through the puncture site. Alternately, thehole is closed by hand suturing. Alternately, the hole is closed with abiocompatible glue, adhesive or the like. Alternately, the hole isclosed with a clip, clamp, or other implantable device that remains onthe target vessel. Such a device may be positioned on the outer surfaceand/or inner surface of the target vessel, and may extend into the hole.A device for closing the hole may be constructed from nitinol or othersuperelastic or pseudoelastic material, or from stainless steel or othermaterial, where that device moves between a first configuration and asecond configuration during deployment, and where the secondconfiguration holds the hole closed. The hole is less than substantially2 mm wide, and advantageously less than 1 mm wide. Alternately, theanvil arm 14 has a blunt distal end 28 that is inserted through a holecreated with a separate instrument, by a different instrument connectedto the anvil arm 14, or by a sharp member connected to the anvil arm 14that can be retracted into the anvil arm 14 or otherwise blunted orconcealed after puncturing or creating an incision in the wall of thetarget vessel.

Once the anvil arm 14 has been inserted into the target vessel 30, theanvil arm 14 may be pulled against an inner wall of the target vessel30, causing tenting of the thin tissue of the vessel wall as illustratedin FIG. 3. This tenting of the vessel wall provides control over theanastomosis site during an anastomosis procedure that is described withrespect to FIGS. 4-6. However, tenting of the target vessel wall neednot be tented in order to control the anastomosis site during theanastomosis procedure.

As shown in FIG. 4, a graft vessel 32 is advanced to the anastomosissite and an end 34 of the graft vessel 32 is positioned adjacent anexterior surface of the target vessel 30 at the anastomosis site. Thetented portion of the target vessel 30 is positioned within theperimeter of the end 34 of the graft vessel 32. As shown in FIG. 5, astaple holder 38 is provided having two arms 40 which are pivotallyconnected to the handle 12 of the anvil 10. Alternatively, the pivotingarms 40 of the staple holder 38 may be connected to the handle 12 in adifferent way, or may be connected to a separate or additional device.The arms 40 are spaced apart from one another across at least a part oftheir length. Thus, the graft vessel can be positioned between the arms40. That is, the arms 40 are positioned on substantially opposite sidesof the graft vessel. In this way, each arm 40 may be positioned againsta flap at an end of the graft vessel, as illustrated in FIGS. 29-31. Thearms 40 may be configured differently, if desired.

Referring also to FIG. 1, the staple holder 38 may be used to holdindividual staples 22 and/or staple holding strips 24. In oneembodiment, each arm 40 of the staple holder 38 carries one row ofstaples 22 or one staple holding strip 24, where the staples 22 arearranged in a substantially linear row. Alternately, staples 22 orstaple strips 24 may be arranged in two or more rows, parallel orotherwise, on one or more arms 40. Alternately, the staples 22 may bestaggered on one or more arms, such that at least one row of staples 22does not fall along a straight line. The staples 22 or staple strips 24may be arranged or aligned in any manner on each arm 40 that results ina secure anastomosis between the graft vessel and the target vessel. Thestaples 22 are inserted through the flaps at the end of the graft vessel32, or another portion of the target vessel, and into the target vessel30 by pivoting the arms 40 of the staple holder 38 towards the anvil arm14. The staple bending features 16 are positioned in a configurationcorresponding to the configuration of the staples 22, such that eachstaple 22 engages a corresponding staple bending feature 16 duringdeployment. When the ends of the staples 22 engage the staple bendingfeatures 16 on the anvil arm 14, the ends of the staples 22 are bentover, securing the graft vessel 32 and target vessel 30 together. Oncethe staple ends are bent over, the staples 22 are released from thestaple holding strip 24 or the staple holder 38, resulting in spacedapart staples 22 securing the graft vessel 32 and the target vessel 30together as shown in FIG. 6. Alternately, the staple holder 38 is aconnector deployer that deploys connectors other than or in addition tostaples 22.

After stapling is complete, an incision is formed in the wall of thetarget vessel 30 to allow blood flow between the target vessel and thegraft vessel 32. Some examples of methods and devices for forming theincision will be described in further detail below. FIG. 6 illustrates acompleted anastomosis between a target vessel 30 and a graft vessel 32with a plurality of staples 22. The spacing between the staples 22 isapproximately 1 to 4 mm. This spacing is similar to the spacing betweensutures in a conventional sutured anastomosis. A different spacingbetween the staples 22 may be used if desired. After completion of theanastomosis, the anvil arm 14 is withdrawn from the target vessel 30between adjacent staples 22. The withdrawal of the anvil arm 14 leaves agap that is approximately the same as the spacing between adjacentstaples. Accordingly, substantially no blood leakage occurs at thelocation where the anvil arm has been withdrawn.

FIGS. 7 and 8 illustrate one example of a staple 22 connected to astaple holding strip 24. This staple 22 includes barbed staple ends 52extending from the front portion of the staple 22 and a C-shaped portion54 extending from a rear of the staple 22 for connecting the staple 22to the staple holding strip 24. The staple holding strip 24 includes aplurality of protrusions 56 for receiving the staples 22. The C-shapedportion 54 of each staple 22 is received around one of the protrusions56 and is secured in place at one or more locations, such as by welds 58or by a frangible linkage or connection. Alternately, the C-shapedportion 54 of each staple 22 may be secured to the staple-holding strip24 in a different way. As shown in FIG. 8, when the staple holding strip24 is advanced toward the anvil arm 14, the barbed staple ends 52 arereceived in the recesses 20 in the anvil arm 14. Contact between eachstaple end 52 and the corresponding recess 20 generates a moment thatcauses the barbed staple ends 52 to bend towards one another. At thesame time that the barbed staple ends 52 bend over, or after the bendingof the staple ends 52, the staple 22 is detached from the staple holdingstrip 24. The staple 22 may be detached from the staple holding strip 24by the action of bending the barbed staple ends 52 such that theC-shaped portion 54 of the staple 22 splays outward and breaks apartfrom the corresponding protrusion 56 on the staple holding strip 24, bybending a frangible connection between the staple holding strip and thestaples to separate the staples, or any other known separation methods,such as melting of a connection between the staple and the stapleholding strip.

FIG. 9 illustrates an alternate staple 22 a having inwardly curvedbarbed staple ends 52 a. Because the staple ends 52 a are themselvescurved, the corresponding staple bending feature or features 16 a neednot be curved to bend the ends 52 a of the staples 22 a. As shown inFIG. 9, the staple bending features 16 a on each side of the anvil arm14 a may be formed as a single longitudinal groove along the anvil arm14 a, where the staple bending feature 16 a has a substantially flatsurface. When the curved ends 52 a of the staple 22 a are received inthe groove 16 a of the anvil arm 14 a, the ends bend inward to securethe tissue with the staple. Alternately, the staple may be configureddifferently. Alternately, two or more different kinds of staples aredeployed by the staple holder 38 in order to form a single anastomosis.

Referring also to FIG. 10A, a plurality of staples 22 a are positionedon an expandable staple holding strip called an expandable backbone 66.The expandable backbone 66 includes a plurality of elements 68 which areinterconnected by one or more expanding members 70. Each of the backboneelements 68 is provided with a connecting diamond member 72 that isconnected to one of the staples 22 a. As shown in FIG. 10A, each staple22 a is connected to the corresponding diamond member 72 by a thinconnecting section 74. The expandable backbone 66 allows the spacingbetween the staples 22 a to be adjusted for the particular anastomosisto be performed. The backbone 66 allows expansion of the distancebetween staples from a distance of approximately 0.1 mm to a distance ofapproximately 1 to 4 mm, i.e., expansion of up to 40 times the originalspacing. Alternately, the backbone 66 allows a different amount ofexpansion. The expanding backbone 66 also includes two openings 76 atopposite ends which may be engaged by holding pins (not shown) on ananastomosis system or staple holder. The opening 76 allow the backbone66 to be easily expanded by relative motion of the holding pins. Theconnecting diamond members 72 are configured to collapse inwardly towardthe backbone when the staples 22 a engage the staple bending surface orsurfaces 16 a of the anvil. The collapsing of each diamond member 72forces the corresponding staple 22 a to separate from the diamond member72 at a connecting section 74. The connecting section 74 is a frangiblelinkage connecting a staple 22 a to a corresponding diamond member 72.

FIG. 10B illustrates another example of staples 22 a detachablyconnected to a backbone 66. The staples 22 a are each connected to theassociated backbone elements 68 at two connecting sections 74. Thestaples 22 a, backbone 66, and associated components are substantiallyas described above with regard to FIG. 10A.

FIG. 11 shows a portion of an anvil arm 14 with a movable cutting device44. The cutting device 44 includes a base 46 and a blade 48. The base 46of the cutting device 44 is positioned in a longitudinal groove 50 inthe anvil arm 14. After the anvil arm 14 has been inserted into thetarget vessel, the cutting device 44 may be moved longitudinally alongthe anvil arm 14 to form an incision in the target vessel.

FIGS. 12, 12A, and 12B illustrate external cutting devices that areadvanced down onto the anvil arm 14 after the anastomosis procedure andcut an incision in the target vessel from an exterior of the targetvessel as the anvil arm 14 is withdrawn. As shown in FIG. 12, a knife 62is positioned on a knife arm 64 that is movable along the handle 12 ofthe anvil. The knife 62 is moved downward in a direction substantiallyparallel to the longitudinal axis of the handle 12 until the knife 62engages a recess 65 in the anvil arm 14. The knife 62 is therebypositioned substantially at the anastomosis site. The end of the graftvessel is then placed substantially against the wall of the targetvessel at the anastomosis site, over the knife 62 and knife arm 64. Asthe anvil arm 14 is withdrawn from the anastomosis site, the knife 62forms an incision in the target vessel. The knife 62 and knife arm 64exit the anastomosis site via the joint between the graft vessel and thetarget vessel. The withdrawal of the anvil arm 14, knife 62 and knifearm 64 leaves a gap in the wall of the target vessel that isapproximately the same as the spacing between adjacent staples tominimize or eliminate leakage through that gap. Alternately, the knife62 may be moveable relative to the handle 12 in at least one directionin addition to a direction substantially parallel to the longitudinalaxis of the handle 12. For example, the knife 62 may be moveable in adirection substantially parallel to the wall of the target vessel tocreate an arteriotomy in the target vessel at the junction between thegraft vessel and the target vessel.

FIGS. 12A and 12B illustrate two alternate examples of the knife 62which snap onto a corresponding engagement surface 65 of the anvil arm14 so that the knife and anvil are secured together for formation of theincision during removal of the anvil arm 14 from the anastomosis site.

FIGS. 13-16 illustrate two variations of extendable cutting devices formaking an incision in the target vessel while withdrawing the anvil arm14 from the target vessel. FIG. 13 illustrates an anvil arm 14 b havinga blade 78 connected to a flexible blade support 80. When the bladesupport 80 is pulled in the direction of the arrow A with respect to theanvil arm 14 b, the blade 78 moves from a forwardly extending positionshown in FIG. 13 to an upwardly extending position shown in FIG. 14 as aresult of flexure of the blade support 80. The blade 78 in the forwardlyextending position may be used to form a small opening in the wall ofthe target vessel through which the anvil arm 14 is inserted into thetarget vessel. After an anastomosis has been performed, or while ananastomosis is performed, the blade 78 is moved to an upwardly angled ora vertical position in which the blade 78 is used to form an incision inthe target vessel as the anvil arm 14 b is removed from the targetvessel.

FIGS. 15-16 illustrate an alternate example of an anvil arm 14 c havinga blade 84 and a blade support 86. While the anvil arm 14 c is insertedinto the target vessel and during the anastomosis procedure, the blade84 is positioned in a recess 88 in the anvil arm. The blade 84 may bemoved from the position of FIG. 15 to the extended position of FIG. 16by moving the blade support 86 in the direction of the arrow B withrespect to the anvil arm. The blade 84 is flexible and stressed, suchthat freeing the blade 84 from the recess 88 causes the blade 84 to moveto the extended position. Alternatively, the blade 84 may be extendedautomatically upon withdrawal of the anvil arm 14 when a blade tip 90catches on an interior surface of the target vessel wall duringwithdrawal of the anvil arm.

The extendable cutting devices shown in FIGS. 13-16 are merely shown asexamples of the type of cutting devices which may be used for making theincision. Once these cutting devices or blades have been extended fromthe anvil arm, they may be fixed to perform cutting as the anvil arm isremoved from the target vessel or the blades may be movable along theanvil arm to make an incision prior to removal of the anvil arm from thetarget vessel.

Another embodiment of the anvil 10 also includes a cutter 200 that ismoveable relative to the anvil 10 for making an incision in the wall ofa target vessel. Referring to FIGS. 34 and 35, a tissue stop 220 isformed into or connected to the anvil 10. The portion of the anvil 10distal to the tissue stop 220 is configured to penetrate into the wallof a target vessel, and may be referred to as the anvil arm 14. Achannel 246 is defined within the anvil arm 14, through which a cutter200 is configured to move. The cutter 200 is narrower than the channel246, such that interior surfaces 202 on either side of the channel 246may guide the translation of the cutter 200 relative to the anvil arm14. As used in this document, the term “translation” as used in regardto the cutter 200 refers to motion of the cutter 200 in the distal orproximal direction, whether or not the cutter 200 or a portion thereofmoves upward or downward during that motion. For convenience, thedirection substantially perpendicular to the longitudinal centerline ofthe anvil arm 14 toward the wall of the target vessel may be referred toas “upward”, and the direction substantially perpendicular to thelongitudinal centerline of the anvil arm 14 away from the wall of thetarget vessel may be referred to as “downward”. However, the positioningof the anvil arm 14 in use is not limited to an orientation in whichthese directions correspond to absolute directions measured relative tothe ground. Similarly, for convenience, motion upward or downward may bereferred to as “vertical” motion, and motion substantially parallel tothe longitudinal centerline of the anvil arm 14 may be referred to as“horizontal” motion.

The anvil arm 14 includes a contact surface 206. Referring also to FIG.36, in use, the contact surface 206 of the anvil arm 14 is placedsubstantially against the inner surface 203 of a target vessel 201. Thecontact surface 206 substantially defines a place that is substantiallyparallel to the longitudinal centerline of the anvil arm 14.Alternately, the contact surface 206 is contoured and/or orienteddifferently. An upper opening 248 extends along at least a portion ofthe contact surface 206 in a direction substantially parallel to thelongitudinal centerline of the anvil arm 14, and opens into the channel246. The upper opening 248 may divide the contact surface 206 intosymmetrical or asymmetrical sections. Further, the contact surface 206may be formed by two substantially planar surfaces, by one substantiallyplanar surface and a differently-shaped surface, or by another set ofsurfaces. Additionally, the contact surface 206 may be formed by twothin edges, each edge occurring at the intersection of a wall of theupper opening 248 and an outer surface of the anvil arm 14. The upperopening 248 need not extend proximally any further than the tissue stop220. However, the upper opening 248 may extend proximal to the tissuestop 220, if desired. A first lower opening 254 and a second loweropening 268 are defined through a lower surface 256 of the anvil arm 14.The lower surface 256 of the anvil arm 14 may be substantially parallelto the contact surface 206 or may be oriented differently relative tothe contact surface 206. Alternately, the first lower opening 254 and/orthe second lower opening 268 do not extend completely through the anvilarm 14, and instead are depressions extending along at least part of abottom surface 266 of the channel 246

Referring also to FIGS. 37-38, the cutter 200 is a thin, rigid member,shaped such that it can be held within the channel 246 in the anvil arm14. The cutter 200 has a substantially constant width along its entirelength. Alternately, the width of the cutter 20 may vary along itslength. The cutter 200 may be made of metal, ceramic, plastic, or othermaterial, or from a combination of different materials. A sharpprojection 208 extends upward from the cutter 200 at or near its distalend. The projection 208 is substantially triangular, but may be shapeddifferently. The projection 208 may be smooth or serrated, or otherwiseshaped or formed. A portion of the projection 208 may be ground orotherwise honed to a sharp edge to facilitate the motion of theprojection 208 through the tissue of the wall of a target vessel, asdescribed in greater detail below. If so, the cutter 200 is composed ofa material that can be sharpened adequately to cut tissue. Alternately,the cutter 200 may be flexible, at least in part. Further, theprojection 208 may be located at a different position on the cutter 200than at or near its distal end. An additional sharp point (not shown)may be provided at the distal end of the cutter 200, extending in adistal direction, in order to create an initial puncture or incision inthe wall of the target vessel. Such a point may be as described in U.S.patent application Ser. No. 10/134,081, which is herein incorporated byreference in its entirety.

One or more additional projections 208 may be provided, if desired. Forexample, two or more projections 208 may extend upward from the cutter200. Where multiple projections 208 are used, they may cooperate withone another to create an incision in the wall of the target vessel.Referring also to FIG. 39, a second projection 208 extends upward fromthe cutter 200 proximal to a first projection 208. The projections 208are both substantially the same triangular shape and the same size.However, the projections 208 may be shaped and sized differently. Theprojections 208 are both substantially planar, and are aligned such thatboth projections 208 lie in substantially the same plane. Eachprojection 208 may include at least one sharpened or beveled edge 209oriented to engage and incise the wall of the target vessel when thecutter 200 is translated, as described below. Referring to FIG. 40, atleast two projections 208 extend upward from the cutter 200. Theprojections 208 each have a barb 211 at the tip. However, the barb 211may be omitted from some or all of the projections 208. Under the barb211, a sharpened or beveled edge 209 extends downward and proximally.The edge 209 may be straight or curved. The upper end of the edge 209 isdistal to the lower, proximal end of the corresponding barb. The edge209 of each projection 208 is oriented to engage and incise the wall ofthe target vessel when the cutter 200 is translated. Referring to FIG.41, at least two projections 208 extend upward from the cutter 200, atleast one of which has a barb 211 at its tip. The edge 209 associatedwith each projection 208 is more curved than the edge 209 shown in FIG.40. Alternately, the edge 209 is substantially straight, or gentlycurved, or positioned on a portion of a larger curved segment 213extending downward from and proximal to the barb 211. Referring to FIG.42, a number of projections 208 may be placed along a length of thecutter 200. This length may be comparable to the desired length of theincision in the wall of the target vessel. These projections 208 may besubstantially triangular as shown, or may be shaped differently. Wheremore than one projection 208 is used on the cutter 200, the projections208 need not have the same configuration. For example, projections 208such as the exemplary projections 208 shown in FIGS. 39-41 may be mixedtogether on the same cutter 200. Alternately, one or more of theprojections 208 are moveable relative to the cutter 200, such that oneor more projections 208 can be moved upward or downward relative to thecutter 200.

As another example of a configuration of the projections 208, referringto FIG. 43, the projections 208 extending upward from the cutter 200each are substantially planar, and are aligned such that not all of theprojections 208 lie in the same plane. In such a configuration, theprojections 208 may create a wider incision in the wall of the targetvessel than would be created if the projections 208 were substantiallyaligned. For example, one set of projections 208 may be alignedsubstantially in a first plane, and a second set of projections 208 maybe aligned substantially in a second plane substantially parallel to thefirst plane. The second plane and the first plane may be orienteddifferently relative to one another, if desired. As another example,none of the projections 208 lie in a common plane with one or more otherprojections 208. Referring to FIGS. 39-42, by using multipleprojections, the cutter 200 need not be translated as far to make anincision in the wall of the target vessel as it would if only a singleprojection 208 were used, as described in greater detail below.

Referring back to FIGS. 34-35, an interior surface 202 is located oneach side of the channel 246. Each interior surface 202 may besubstantially planar, curved, or may be shaped differently. Further,each interior surface 202 may be oriented at an angle to vertical orsubstantially vertical. The interior surfaces 202 may be formed suchthat the channel 246 is substantially bilaterally symmetrical, or may beformed to result in a channel 246 that is not bilaterally symmetrical.The interior surfaces 202 of the channel 246 within the anvil arm 14 mayinclude raised features 204 that correspond to depressed staple bendingfeatures (not shown) on the outer surface of the anvil arm 14. That is,if the staple bending features are stamped into the anvil arm 14, orformed in another way that causes deformation of the anvil arm 14, thedepressed staple bending features result in corresponding raisedfeatures 204 on the interior surface 202 of the channel 246. The raisedfeatures 204 do not interfere with the motion of the cutter 200 throughthe channel 246. Alternately, the raised features 204 are not present onthe interior surface 202 of the channel 246.

A safety feature 210 is connected to the underside of the anvil 10 andis biased toward the anvil 10 and the cutter 200. The safety feature 210may be biased into the channel 246 within the anvil 10. Alternately, thesafety feature 210 is connected to a different location, such as theunderside of the anvil arm 14. The safety feature 210 may be flexible orrigid. The safety feature 210 includes a tip 212 that is orientedsubstantially transverse to the longitudinal centerline of the cutter200. Alternately, the tip 212 may be oriented in a different direction.The cutter 200 includes a safety recess 214 defined in it, correspondingto the tip 212 of the safety feature 210. The tip 212 is shaped andsized such that it can engage the safety recess 214. The tip 212 may bea bar or rod oriented substantially transverse to the direction oftranslation of the cutter 200, or may be shaped or oriented differently.In FIG. 34, the staple holder 38 has not yet been moved into position toperform anastomosis. In this position, the tip 212 of the safety feature210 is biased upward to engage the safety recess 214. The engagementbetween the safety recess 214 and the tip 212 of the safety feature 210substantially prevents translation of the cutter 200 within the channel246. Thus, the cutter 200 and the projection 208 are prevented fromdeploying until the staple holder 38 has been moved into the appropriateposition relative to the anvil arm 14, and inadvertent deployment of thecutter 200 is prevented.

The cutter 200 includes an engagement member 216 extending upward from alocation at or near its proximal end. The engagement member 216 insteadmay extend downward from the cutter 200 or to the side of the cutter200. Further, the engagement member 216 may be positioned at a locationother than at or near the proximal end of the cutter 200. The engagementmember 216 is configured to engage at least a portion of a correspondingreceiver 218 in the staple holder 38. Thus, after engagement between theengagement member 216 and the receiver 218, translation of the receiver218 results in translation of the cutter 200. The receiver 218 is astructure that is at least partially open on its underside and thatincludes at least one surface 219 configured to engage the engagementmember 216. As shown in FIG. 34, the surface 219 is a partially-curvedsurface shaped to receive the curved upper end of the engagement member216. However, the receiver 218 may be a flat vertical surface, a curvedsurface, a structure such as an inverted cup that is open on itsunderside and that has a wall or walls encircling the engagement feature216, or any other structure or mechanism capable of engaging theengagement feature 216 and urging it distally.

An anvil insert 222 is fixed to the anvil 10. Alternately, the anvilinsert 222 is connected to and capable of motion relative to the anvil10. Further, the anvil insert 222 may be connected to the proximal endof the anvil arm 14, or another location on the anvil arm 14. A cavity228 is defined within the anvil insert 222. An aperture 230 is definedthrough the distal end of the anvil insert 222 into the cavity 228,connecting the channel 246 in the anvil arm 14 and anvil 10 to thecavity 228. The cutter 200 extends through the aperture 230, such thatthe distal end of the cutter 200 is positioned within the channel 246and the proximal end of the cutter 200 is positioned within the cavity228.

A cutter stop 236 may be formed into or connected to the anvil insert222. The cutter stop 236 may engage the proximal end of the cutter 200if the cutter 200 is moved to a defined position within the cavity 228,thereby restricting its proximal translation. A cavity 262 may bedefined within the staple holder 38 or a separate component connected tothe staple holder 38. A post 258 is positioned at the upper end of thecavity 262, where the post 258 is oriented downward. A biasing element260 is connected at one end to the post 258. The biasing element 260 maybe a coil spring, a leaf spring, a different type of spring, anelastomer, a wire form, or other structure or mechanism capable ofexerting a biasing force. The biasing element 260 is positioned withinand protected by the cavity 262, where the cavity 262 is used. Thecavity 262 may be a cylindrical opening having a diameter substantiallythe same as the outer diameter of the biasing element 260, such that thecavity 262 restricts the biasing element 260 to motion substantiallyalong the axis of the cavity 262 and thus directs the force exerted bythe biasing element 260 in a substantially downward direction,preventing bending or other undesirable motion of the biasing element260. The end of the biasing element 260 that is not connected to thepost 258 contacts the cutter 200. As an example, the biasing element 260may be a compression spring that is compressed between the post 258 andthe cutter 200, resulting in a force on the cutter 200 that biases thecutter 200 downward. The cutter 200 is slidable relative to the biasingelement 260, such that the biasing element 260 exerts a downward forceon the cutter 200 at different locations along its upper surface 252 asthe cutter 200 translates. Thus, at least the distal end of the cutter200 is biased downward throughout its translation along the anvil 10.The entire cutter 200 may be biased downward, if desired. Alternately,the post 258 is omitted, and the biasing element 260 is fixed to anupper surface of the cavity 260. Alternately, the biasing element 260 isomitted, and the cutter 200 is biased downward in another way. Forexample, the cutter 200 may be constructed from an elastic orsuperelastic material that is formed in such a way as to produce adownward bias.

As shown in FIG. 34, the distal end of the anvil arm 14 initially isspaced apart from the staple holder 38. While the distal end of theanvil arm 14 is spaced apart from the staple holder 38, the anvil arm 14is inserted through the wall of the target vessel, which is not shownfor clarity. Advantageously, the anvil arm 14 has a cross-section smallenough to allow it to enter the target vessel easily and to result inminimal or no leakage from the target vessel after the anvil arm 14 isremoved. The distal tip of the anvil arm 14 may be sharp such that theanvil arm 14 itself penetrates the wall of the target vessel, resultingin an opening in the wall of the target vessel substantially the samesize as the cross-section of the anvil arm 14. Alternately, a sharpretractable projection (not shown) is provided at the distal end of theanvil arm 14. The retractable projection is extended to allow the distalend of the anvil arm 14 to penetrate the wall of the target vessel, thenretracted into the anvil arm 14. The retractable projection may be awire, a blade, a substantially conical member, a screw or a screw-tippedrod, or any other sharp structure or mechanism capable of penetratingthe wall of the target vessel. Such a retractable projection may be asdescribed in U.S. patent application Ser. No. 10/134,081, which isherein incorporated by reference in its entirety. Alternately, thecutter 200 includes a blade (not shown) at its distal end, where theblade is configured to swivel. In a first position, the blade isconfigured to extend substantially distal to the distal end of the anvilarm 14, such that the blade can penetrate the wall of the target vessel.Then, the blade is swiveled upward such that it can act as a protrusion208 such as described in FIGS. 39-42. Alternately, a separate mechanismor structure is used to penetrate the wall of the target vessel, and theanvil arm 14 is later inserted through that penetration.

Referring also to FIG. 36, after insertion, the distal end of the anvilarm 14 enters the lumen of the target vessel. The anvil arm 14 isadvanced into the target vessel until a tissue stop 220 on the anvil arm14 encounters the edge of the penetration in the wall of the targetvessel. The tissue stop 220 is substantially flat and/or blunt, andextends upward or in another direction relative to the anvil arm 14 toincrease the height and/or width of the anvil arm 14. The tissue stop220 increases the cross-section of the anvil arm 14 such that the anvilarm 14 cannot easily move further into the penetration in the wall ofthe target vessel after the tissue stop 220 encounters the outer wall ofthe target vessel. Because the tissue stop 220 is blunt, it does notpenetrate the wall of the target vessel or act to expand the size of theexisting penetration. Thus, the distance between the distal end of theanvil arm 14 and the tissue stop 220 substantially determines how muchof the anvil arm 14 is allowed into the lumen of the target vessel.After the anvil arm 14 has been inserted into the lumen of the targetvessel, the contact surface 206 of the anvil arm 14 is substantially incontact with the inner surface of the wall of the target vessel.

Next, referring also to FIG. 44, the staple holder 38 and the anvil 10are rotated or otherwise moved closer to one another to a standbyposition. As the staple holder 38 and anvil 10 move closer together, thestaple holder 38 holds flaps at the end of the graft vessel, which areconfigured substantially as shown in FIGS. 29-31, against the surface ofthe target vessel at the site of the anastomosis. The flaps aresubstantially fixed relative to the surface of the target vessel, suchthat the end of the graft vessel is substantially immobile relative tothe wall of the target vessel. Thus, the position of the end of thegraft vessel relative to the wall of the target vessel remainssubstantially unchanged throughout the duration of the anastomosisprocedure. The perimeter of the end of the graft vessel defines a closedarea on the wall of the target vessel. Consequently, the location of aconnection made between the end of the graft vessel and the wall of thetarget vessel is substantially registered with an opening made withinthe closed area in the wall of the target vessel, regardless of theorder in which the connection and the opening are made. Further, theposition of the end of the graft vessel relative to the wall of thetarget vessel substantially maintains position registration throughoutthe duration of the anastomosis procedure relative to the opening in thewall of the target vessel through which the anvil arm 14 is inserted.For clarity, the flaps and graft vessel are not shown in FIG. 44. Thestaple holder 38 and anvil 10 may be actuated to move between theposition shown in FIG. 34 and the position shown in FIG. 44 by anystructure, mechanism or method. As one example, a cable (not shown) isconnected to the anvil 10 at or near a shoulder 224 proximal to thetissue stop 220. This connection may be made by soldering, welding,winding the cable tightly around the anvil 10 at the shoulder 224, or inany other way that results in a secure connection between the cable andthe anvil 10. To move the anvil 10 and the staple holder 38 relative toone another, the cable is tensioned, causing the anvil 10 and/or theconnected anvil insert 222 to rotate around a pivot point such as a pin226 that pivotally connects the staple holder 38 to the anvil 10. Thepin 226 may be formed into or otherwise fixed to the staple holder 38 oranvil arm 14, if desired. Thus, the anvil 10 and the staple holder 38rotate relative to one another to the standby position.

As the staple holder 38 and anvil 10 move together, the engagementmember 216 engages the receiver 218. Further, the relative motion of thestaple holder 38 and the anvil 10 causes the staple holder 38 to contactthe safety feature 210 and urge it downward against its upward bias.Consequently, the tip 212 of the safety feature 210 is moved downwardout of engagement with the safety recess 214 of the cutter 200.Alternately, another structure or mechanism is configured to engage thesafety feature 210 when the staple holder 38 and anvil 10 are movedtogether, so as to urge the tip 212 out of the safety recess 214. Thus,in the standby position, the cutter 200 is freed for translation alongthe channel 246

Optionally, an interface structure 238 may be connected to or formedinto the staple holder 38. The interface structure 238 engages the anvil10 or a component associated with the anvil 10 as the staple holder 38and the anvil 10 move to the standby position, such as by snapping ontoa corresponding feature (not shown) on the anvil 10. By doing so, theinterface structure 238 holds the staple holder 38 substantially fixedrelative to the anvil 10, in order to maintain registration between thetarget vessel, the graft vessel, the anvil 10 and the staple holder 38.The interface structure 238 may be a tab, rail, bump, or any otherfeature that is capable of engaging a corresponding feature and holdingthe staple holder 38 substantially fixed relative to the anvil 10.Alternately, the interface structure 238 is formed into or connected tothe anvil 10 and engages a corresponding feature on the staple holder38.

Referring also to FIG. 45, after the cutter 200 has been freed fortranslation, the cutter 200 is urged distally relative to the anvil arm14. Advantageously, the staple holder 38 has stapled or otherwiseconnected the graft vessel to the target vessel before the cutter 200 isurged forward, such that the two vessels are connected before the cutter200 makes an incision between them. Alternately, the cutter 200 may beurged forward while the staple holder 38 is stapling or otherwiseconnecting the graft vessel to the target vessel, or before the stapleholder 38 has stapled or otherwise connected the graft vessel to thetarget vessel.

The cutter 200 is urged distally by the receiver 218, which engages theengagement feature 216 of the cutter 200. The receiver 218 is configuredto travel along a guide structure 241. The guide structure 241 is a railor other structure along which the receiver 218 slide, and the receiver218 interfaces with and translates along the rail. Thus, the guidestructure 241 guides the translation of the receiver 218. Alternately,the guide structure 241 is a hollow channel defined within the stapleholder 38, such that the walls of the channel guide the translation ofthe receiver 218. Alternately, the guide structure 241 may be any otherstructure or mechanism capable of guiding the translation of thereceiver 218. The guide structure 241 is substantially aligned with theanvil arm 14. That is, the longitudinal centerline of the guidestructure 241 is substantially parallel to the longitudinal centerlineof the anvil arm 14. Thus, motion of the receiver 218 along the guidestructure 241 causes translation of the engagement feature 216 andtherefore translation of the cutter 200 substantially parallel to thecenterline of the anvil arm 14. The receiver 218 may be actuated totranslate along the guide structure 241 by an actuator (not shown). Theactuator may directly transmit force from a human hand or the like tothe cutter, such as via a cable (not shown). The cable may be the samecable described above that may be utilized to rotate the anvil 10 andstaple holder 38 relative to one another, or may be a different cable.Alternately, the actuator may convert stored energy to force that isapplied to the cutter. Such stored energy may be provided by a spring,battery, source of compressed gas, or other source. Alternately, anymechanism, structure or method, using stored energy or not, may be usedto translate the receiver 218 along the guide structure 241. Theparticular mechanism, structure or method used to cause translation ofthe cutter 200 is not critical to the invention. A cavity 240 isprovided in the staple holder 38 adjacent to the guide structure 241 toallow for motion of the receiver 218 along the guide structure 241. Thecavity 240 is sized to allow the receiver 218 to translate freely.

The upper surface 252 of the cutter 200 is substantially planar proximalto the projection 208. The biasing element 260 contacts the uppersurface 252 of the cutter 200 and biases the cutter 200 downward. Thecutter 200 includes a keel 264 that extends downward. The keel 264 maybe formed into the cutter 200, or may be a separate component connectedto the cutter 200. The keel 264 is substantially as wide as the adjacentportion of the cutter 200. However, the keel 264 may be wider ornarrower than the adjacent portion of the cutter 200. The keel 264 ispositioned at or near the distal end of the cutter 200. Alternately, thekeel 264 may be positioned at a different location on the cutter 200.

As shown in FIG. 45, the keel 264 initially extends into the first loweropening 254, which is defined through a lower surface 256 of the anvil10. The keel 264 may extend completely through the first lower opening254, such that its lowest point extends outside the anvil 10. The keel264 is biased downward into the first lower opening 254 as a result ofthe downward force exerted on the cutter 200 by the biasing element 260.While the keel 264 is biased into the first lower opening 254, theprojection 208 remains below the contact surface 206 of the anvil arm14. In this way, the projection 208 does not extend out of the anvil arm14 while the anvil arm 14 is inserted into the wall of a target vessel.The first lower opening 254 extends along a fixed length of the lowersurface 256 of the anvil 10. As the cutter 200 translates distally, thekeel 264 continues to remain at least partially within the first loweropening 254, such that the projection 208 continues to remain below thecontact surface 206 of the anvil arm 14. Initially, the keel 264 may bepositioned proximal to the distal end of the first lower opening 254.The length of the first lower opening 254 is selected to cause theprojection 208 to remain below the contact surface 206 of the anvil arm14 across that distance. That is, this distance is selected such thatthe projection 208 on the cutter 200 does not engage the wall of thetarget vessel until the projection 208 is positioned within thecircumference of the graft vessel. That is, the connection between thegraft vessel and the target vessel substantially defines a closed area,and the projection 208 is configured to engage the wall of the targetvessel within that closed area. In this way, the projection 208 makes anincision completely within the connection between the graft vessel andthe target vessel, completing the anastomosis between the two vesselsand minimizing or eliminating leakage at the anastomosis site. While theprojection 208 on the cutter 200 remains below the upper surface of theanvil arm 14, it neither engages nor cuts the wall of the target vessel.

Referring also to FIG. 46, the cutter 200 continues to advance distallyas the receiver 218 continues to impel the engagement feature 216distally. As described above, at least the distal end of the cutter 200is biased downward. As the cutter 200 advances distally, the keel 264encounters the distal end of the first lower opening 254. Thisencounter, and the continued proximal translation of the cutter 200,causes the keel 264 to move upward relative to the anvil arm 14. Thekeel 264 and/or the distal end of the first lower opening 254 may beconstructed to provide a smooth, gradual upward motion of the keel 264,such as by providing a gradual slope on the keel 264 and/or the distalend of the first lower opening 254. Alternately, the keel 264 and/or thedistal end of the first lower opening 254 may be constructed to allow orcause the keel 264 to move upward abruptly upon encountering the distalend of the first lower opening 254. The upward motion of the keel 264causes the distal end of the cutter 200 and the projection 208 to moveupward. Thus, the size and position of the first lower opening 254,including the position of the distal end of the first lower opening 254,control the motion of the cutter 200 and the projection 208 in thevertical direction.

As the distal end of the cutter 200 moves upward, the projection 208moves upward through the upper opening 248 in the anvil arm 14. Thecontact surface 206 of the anvil arm 14 is substantially adjacent to theinner surface of the wall of the target vessel. Thus, upward motion ofthe projection 208 through the upper opening 248 and above the contactsurface 206 of the anvil arm 14 causes the projection 208 to enter thewall of the target vessel. The cutter 200 continues to move distally,such that the keel 264 moves out of the first lower opening 254completely and contacts the bottom surface 266 of the channel 246 of theanvil arm 14. The projection 208 is sized such that the projection 208completely penetrates the wall of the target vessel when the keel 264has moved proximally to the first lower opening 254 and is in contactwith the bottom surface 266 of the channel 246. That is, at least aportion of the projection 208 passes through the wall of the targetvessel and enters the lumen of the target vessel. This initialpenetration of the wall of the target vessel defines the starting pointof an arteriotomy performed on the target vessel by the projection 208.The starting point of the arteriotomy is spaced apart from the locationon the target vessel at which the anvil arm 14 is inserted, because thecutter 200 and the projection 208 have moved proximally a selecteddistance before penetrating or incising the wall of the target vessel.The portion of the wall of the target vessel between the arteriotomy andthe insertion point of the anvil arm 14 may be referred to as a tissuebridge. The incision is referred to as an arteriotomy for convenience,and this terminology does not limit the type of anastomosis that may beperformed. For example, anastomosis may be performed between two tissuestructures that are not blood vessels, such as bile ducts.

Referring also to FIG. 47, the cutter 200 continues to advance distallyas the receiver 218 continues to impel the engagement feature 216distally. The lower surface of the keel 264 contacts the bottom surface266 of the channel 246 during this translation. The contact between thekeel 264 and the bottom surface 266 of the channel 246 counteracts thedownward bias of the distal end of the cutter 200. In this way, theprojection 208 is maintained above the contact surface 206 of the anvilarm 14. As the cutter 200 continues to translate distally, theprojection 208 moves through the tissue of the wall of the target vesselin a direction substantially parallel to the longitudinal centerline ofthe anvil arm 14, and incises the tissue of the wall of the targetvessel to create an arteriotomy. Because the projection 208 is connectedto and translated by the cutter 200, which is within the target vessel,the arteriotomy is performed from within the target vessel. The tip ofthe projection 208 may maintain substantially the same height relativeto the contact surface 206 of the anvil arm 14 during translation of thecutter 200, or may change its height relative to the contact surface 206of the anvil arm, as long as the projection 208 continues to incisecompletely through the wall of the target vessel.

Referring also to FIG. 48, a second lower opening 268 is defined throughthe lower surface 256 of the anvil arm 14. The second lower opening 268is distal to and substantially aligned with the first lower opening 254.The cutter 200 continues to advance distally as the receiver 218continues to impel the engagement feature 216 distally. As a result ofthis translation, the keel 264 encounters the proximal end of the secondlower opening 268. Because the distal end of the cutter 200 is biaseddownward, the keel 264 moves downward at least partially into the secondlower opening 268. The downward motion of the keel 264 causes the distalend of the cutter 200 and the projection 208 to move downward. The keel264 and/or the proximal end of the second lower opening 268 may beconstructed to provide a smooth, gradual downward motion of the keel264, such as by providing a gradual slope on the keel 264 and/or theproximal end of the second lower opening 268. Alternately, the keel 264and/or the proximal end of the second lower opening 268 may beconstructed to allow or cause the keel 264 to move downward abruptlyupon encountering the proximal end of the second lower opening 268. Thedownward motion of the distal end of the cutter 200 causes theprojection 208 to retract into or completely through the upper opening248, such that the projection 208 no longer encounters the tissue of thewall of the target vessel. The projection 208 may be urged downwardcompletely into the channel 246, depending on the depth of the channel246 and the height of the projection 208. Alternately, the upper tip ofthe projection 208 may remain within the upper opening 248. The cutter200 may stop its distal translation at substantially the same time thatthe projection 208 retracts completely into the upper opening 248, ormay continue to translate distally within the channel 246 before comingto a stop. Alternately, the second lower opening 268 is not provided,and only the first lower opening 254 extends through the lower surface156 of the anvil arm 14 into the channel 246. In such a configuration,the cutter 200 is retracted in the proximal direction after thearteriotomy is formed, until the keel 264 moves downward into the firstlower opening 254 and the projection 208 consequently retractscompletely into the upper opening 248.

When the projection 208 is retracted out of the tissue of the wall ofthe target vessel, the distal end of the arteriotomy is defined, and thearteriotomy is complete. The distal end of the first lower opening 254and the proximal end of the second lower opening 268 control the motionof the projection 208 and thereby control the penetration of the wall ofthe target vessel. That is, the distance between the distal end of thefirst lower opening 254 and the proximal end of the second lower opening268 determines the length of the arteriotomy.

After performing the arteriotomy, the cutter 200 is in adistally-extended position. The cutter 200 remains in that position asthe anvil arm 14 is removed from the target vessel. Thus, the projection208 does not extend out of the upper opening 248 during removal of theanvil arm 14 from the target vessel. The anvil arm 14 is removed fromthe target vessel after the anastomosis between the graft vessel and thetarget vessel has been completed. Alternately, after performing thearteriotomy, the cutter 200 may be moved proximally within the channel246 in the anvil arm 14 before removing the anvil arm 14 from the targetvessel. The hole in the wall of the target vessel 30 through which theanvil arm 14 enters the target vessel is small enough to preventsignificant bleeding through the puncture site. Alternately, the hole isclosed by hand suturing. Alternately, the hole is closed with abiocompatible glue, adhesive or the like. Alternately, the hole isclosed with a clip, clamp, or other implantable device that remains onthe target vessel. Such a device may be positioned on the outer surfaceand/or inner surface of the target vessel, and may extend into the hole.A device for closing the hole may be constructed from nitinol or othersuperelastic or pseudoelastic material, or from stainless steel or othermaterial, where that device moves between a first configuration and asecond configuration during deployment, and where the secondconfiguration holds the hole closed. The hole is less than substantially2 mm wide, and advantageously less than 1 mm wide.

Referring to FIG. 49, another embodiment of the anvil 10 also includes acutter 200 moveable relative to the anvil 10 for making an incision inthe wall of a target vessel. The anvil 10, anvil arm 14, staple holder38, and other components are substantially as described above withregard to FIGS. 34-38 and 44-49. Referring to FIGS. 35 and 49, the anvilinsert 222 is connected to the anvil 10. An aperture 230 is definedthrough the distal end of the anvil insert 222 into the cavity 228defined within the anvil insert 222, connecting the channel 246 to thecavity 228. The cutter 200 extends through the aperture 230 in the anvilinsert 222, such that the distal end of the cutter 200 is positionedwithin the channel 246 and the proximal end of the cutter 200 ispositioned within the cavity 228. A cam 232 is positioned within thecavity 228 above the aperture 230. Alternately, the cam 232 may bepositioned differently relative to the aperture 230. The cam 232 is astructure used in controlling the motion of the cutter 200, as isdescribed in greater detail below.

At least the distal end of the cutter 200 may be biased upward. Thisbiasing may be performed by any appropriate structure or mechanism, suchas by one or more springs (not shown). Such a spring or springs may actin compression to push the distal end of the cutter 200 upward, or mayact in tension to pull the distal end of the cutter upward. As anotherexample, the cutter 200 may be constructed from an elastic orsuperelastic material that is formed in such a way as to produce anupward bias. The entire cutter 200 may be biased upward, if desired. Atleast the distal end of the cutter 200 is biased upward during thetranslation of the cutter 200 along the anvil arm 14. Alternately, thecutter 200 is not biased, either upward or downward. Instead, the cutter200 is urged upward and downward at different locations during itstranslation by the interaction between at least one cam follower on thecutter 200 and at least the cam 232.

As shown in FIG. 49, the distal end of the anvil arm 14 is spaced apartfrom the staple holder 38. The anvil arm 14 is inserted through the wallof the target vessel, as described above, such that the contact surface206 of the anvil arm 14 is in substantial contact with the inner wall ofthe target vessel. Next, referring to FIG. 50, the staple holder 38 andanvil 10 are moved relative to one another into the standby position, asdescribed above. In the standby position, the cutter 200 is freed fortranslation along the channel 246, because the tip 212 of the safetyfeature 210 no longer engages the safety recess 214 of the cutter 200.At least the distal end of the cutter 200 is biased upward, and the cam232 limits the upward motion of the cutter 200 by contacting at least aportion of the upper surface 252 of the cutter 200. The cam 232 controlsthe motion of the distal end of the cutter 200 in the vertical directionas the cutter 200 translates within the channel 246. Because theprojection 208 is fixed to the cutter 200, the cam 232 also controls themotion of the projection 208 in the vertical direction, and thuscontrols the location at which the projection 208 encounters the wall ofthe target vessel.

Referring also to FIG. 51, after the cutter 200 has been freed fortranslation, it is urged distally by the receiver 218 as describedabove. A first cam follower 242 is defined on the upper surface 252 ofthe cutter 200. The first cam follower 242 is a raised structure formedinto the upper surface 252 of the cutter 200. Alternately, the first camfollower 242 is a separate structure or mechanism constructed separatelyfrom the cutter 200 and later connected to the cutter 200. Alternately,the first cam follower 242 may be located on a surface of the cutter 200in addition to or instead of its upper surface 252, depending on theposition and configuration of the cam 232. The first cam follower 242may be shaped as a trapezoid or similar shape, or may be shapeddifferently.

The cam 232 is fixed, and the first cam follower 242 is raised relativeto the upper surface 252 of the cutter 200. At least the distal end ofthe cutter 200 is biased upward. Thus, as the cutter 200 translatesdistally, the cam 232 engages the first cam follower 242 and causes thecutter 200 to move downward. The cam 232 and the first cam follower 242are shaped to smoothly engage each other. Alternately, the first camfollower 242 is shaped to induce the cutter 200 to abruptly movedownward when the first cam follower 242 initially encounters the cam232. The height of the first cam follower 242 relative to the contactsurface 206 of the anvil arm 14 determines the distance that the distalend of the cutter 200 is moved downward. As described above, the cutter200 may include a keel 264 or similar projection extending downward. Asthe distal end of the cutter 200 moves downward, the keel 264 or otherprojection moves into the first lower opening 254. In this embodiment,the first lower opening 254 does not control the motion of the cutter200; instead, it provides a space for the keel 264 to move downwardwithout interfering with the vertical motion of the distal end of thecutter 200. If the keel 264 is omitted, the first lower opening 254 andthe second lower opening 268 may be omitted as well.

The connection between the graft vessel and the target vesselsubstantially defines a closed area, and the projection 208 isconfigured to engage the wall of the target vessel within that closedarea. That is, the end of the graft vessel has a perimeter that contactsthe side of the target vessel, such that the perimeter of the end of thegraft vessel defines a closed area on the wall of the target vessel. Inthis way, the projection 208 makes an incision completely within theconnection between the graft vessel and the target vessel, completingthe anastomosis between the two vessels and minimizing or eliminatingleakage at the anastomosis site. While the projection 208 on the cutter200 remains below the contact surface 206 of the anvil arm 14, itneither engages nor cuts the wall of the target vessel. Thus, the firstcam follower 242 is sized to translate the tip of the projection 208below the contact surface 206 of the anvil arm 14 for a selecteddistance such that the projection 208 does not engage the tissue of thetarget vessel until the projection 208 is positioned to enter the closedarea on the wall of the target vessel defined by the perimeter of theend of the graft vessel.

Referring also to FIG. 52, the cutter 200 continues to advance distallyas the receiver 218 continues to impel the engagement feature 216distally. Thus, the first cam follower 242 of the cutter 200 advancesdistally relative to the cam 232. As described above, at least thedistal end of the cutter 200 is biased upward. The first cam follower242 decreases in height at its proximal end. Thus, as theupwardly-biased first cam follower 242 moves distally relative to thecam 232, the cam 232 and the first cam follower 242 gradually disengage,causing both the distal end of the cutter 200 and the projection 208 tomove upward. The first cam follower 242 is constructed to provide asmooth, gradual upward motion of the distal end of the cutter 200 andthe projection 208, such as by providing a gradual slope between anupper surface 250 of the first cam follower 242 and an upper surface 252of the cutter 200. Alternately, the first cam follower 242 may beconstructed to allow the distal end of the cutter 200 and the projection208 to abruptly snap upward as the first cam follower 242 moves distalto the cam 232.

As the distal end of the cutter 200 moves upward, the projection 208moves upward through the upper opening 248 in the anvil arm 14. Thecontact surface 206 of the anvil arm 14 is adjacent to the inner surfaceof the wall of the target vessel. Thus, upward motion of the projection208 through the upper opening 248 causes the projection 208 to enter thewall of the target vessel. The projection 208 is sized, and the firstcam follower 242 and cam 232 are shaped, such that the upward motion ofthe projection 208 after the first cam follower 242 has moved distal tothe cam 232 causes the projection 208 to completely penetrate throughthe wall of the target vessel. That is, at least a portion of theprojection 208 passes through the wall of the target vessel and entersthe lumen. This initial penetration of the wall of the target vesseldefines the starting point of an arteriotomy performed on the targetvessel by the projection 208. The starting point of the arteriotomy isspaced apart from the location on the target vessel at which the anvilarm 14 is inserted, resulting in a tissue bridge therebetween.

Referring also to FIG. 53, the cutter 200 continues to advance distallyas the receiver 218 continues to impel the engagement feature 216distally. The upper surface 252 of the cutter 200 may contact the cam232 during this motion, because the distal end of the cutter 200continues to be biased upward. As the cutter 200 translates, theprojection 208 moves through the tissue of the wall of the target vesselin a direction substantially parallel to the longitudinal centerline ofthe anvil arm 14. In this way, the projection 208 incises the tissue ofthe wall of the target vessel to create an arteriotomy. The tip of theprojection 208 may maintain substantially the same height relative tothe contact surface 206 of the anvil arm 14 during its distaltranslation, or may change its height relative to the contact surface206 of the anvil arm 14, as long as the tip of the projection 208remains in the lumen of the target vessel during that translation.

Referring also to FIG. 54, a second cam follower 244 is defined on theupper surface 252 of the cutter 200, proximal to and spaced apart fromthe first cam follower 242. Alternately, a single cam follower isdefined on the upper surface 252 of the cutter 200, where that singlecam follower includes a feature corresponding to the first cam follower242, a feature corresponding to the second cam follower 244, and asection of reduced height between them corresponding to the uppersurface 252 of the cutter 200. The cutter 200 continues to advancedistally as the receiver 218 continues to impel the engagement feature216 distally. As a result of this motion, the second cam follower 244contacts the cam 232. Engagement between the second cam follower 244 andthe cam 232 pushes the distal end of the cutter 200 downward. The shapeand size of the second cam follower 244 and cam 232 are selected suchthat the distal end of the cutter 200 is pushed downward far enough tocause the projection 208 to retract into the upper opening 248. Theprojection 208 may be urged downward completely into the channel 246,depending on the depth of the channel 246 and the height of theprojection 208. Alternately, the upper tip of the projection 208 mayremain within the upper opening 248. The cutter 200 may stop its distaltranslation at substantially the same time that the projection 208retracts completely into the upper opening 248, or may continue totranslate distally within the channel 246 before coming to a stop.

When the projection 208 is retracted out of the tissue of the wall ofthe target vessel, the distal end of the arteriotomy is defined, and thearteriotomy is complete. The distance between the first cam follower 242and the second cam follower 244, and the shape of the cam followers 242,244, determine the length of the arteriotomy. That is, each cam follower242, 244 includes a location thereon having a height relative to theupper surface 252 of the cutter 200 sufficient to cause the projection208 to be pushed out of contact with the wall of the target vessel. Thedistance between these locations defines the length of the arteriotomy.Thus, the cam followers 242, 244 control the motion of the projection208 and control the penetration of the wall of the target vessel.

After performing the arteriotomy, the cutter 200 is in adistally-extended position. The cutter 200 remains in that position asthe anvil arm 14 is removed from the target vessel. The anvil arm 14 isremoved from the target vessel after the anastomosis between the graftvessel and the target vessel has been completed. Alternately, afterperforming the arteriotomy, the cutter 200 may be moved proximallywithin the channel 246 before removing the anvil arm 14 from the targetvessel. The hole at the puncture site and its closure are substantiallyas described above.

Alternately, in the embodiment of FIGS. 34-35 and 44-49, or theembodiment of FIGS. 50-54, the cutter 200 is initially in adistally-extended position, and retracted proximally in order to make anincision in the wall of the target vessel. The structures and mechanismsare as described above, but operated in substantially the reverse orderas described above. Alternately, the cutter 200 and the projection 208may be moved in a different way in order to incise the tissue of thewall of the target vessel.

Where multiple projections 208 are provided on the cutter 200 as shownin FIGS. 39-43, the cutter 200 need not be translated as far to make anincision in the wall of the target vessel as it would if only a singleprojection were used. Because the projections 208 are spaced apart fromeach other along the direction of translation of the cutter 200, eachprojection 208 is able to form a portion of the incision duringtranslation of the cutter 200. Thus, by translating each projection 208across a distance less then the intended length of the entire incision,the complete incision can be formed. The distance that the cutter 200 istranslated to form the incision is related to the distance between theprojections 208. That is, because each projection 208 forms a portion ofthe incision, no single projection 208 need be translated along theentire length of the incision.

Alternately, where multiple projections 208 are utilized, theprojections 208 may be inserted into the wall of the target vessel,after which energy is applied to the projections 208 via the cutter 200or directly in order to create an incision in the wall of the targetvessel. In such an embodiment, an energy source (not shown) is connectedto the cutter 200. For example, an ultrasound generator (not shown) maybe connected to the cutter 200 and to the energy source. The ultrasoundgenerator may be a piezoelectric crystal, as is standard, or a differentstructure or mechanism. Electrical energy may be applied to theultrasound generator from the energy source, thereby causing theultrasound generator to vibrate the projections 208. Thus, energy may beapplied from the energy source to the ultrasound generator after theprojections 208 have been inserted into the wall of the target vessel,causing the projections 208 to move and thereby create an incision.Advantageously, a plurality of projections 208 spaced relatively closeto one another are utilized. Other methods may be used to vibrate, moveor oscillate the projections 208. FIGS. 17-23 illustrate an alternateanvil 100 that is used with a clamp 102 for controlling an incision siteduring an anastomosis procedure. As shown in FIGS. 17 and 18, the anvil100 includes an anvil arm 104 and a handle 106. The clamp 102 isslidable on the handle 106 to clamp the tissue of the target vessel 30between the clamp 102 and the anvil arm 104. As with the anvil arm 104described above, the anvil arm 104 includes two rows of staple bendingfeatures 108 in the form of recesses positioned in two parallel rowsalong a top surface of the anvil arm 104. The clamp 102 has a centralopening 110. Once the tissue of the target vessel wall has been trappedbetween the clamp 102 and the anvil arm 104, an incision may be madethrough the target vessel wall and the edges of the incision arecontrolled by the combination of the anvil arm 104 and the clamp 102.

As shown in FIG. 19, a continuous anastomosis staple device 114 may beused to connect the graft vessel 32 to the target vessel 30 at theanastomosis site. The staple device 114 as shown in FIG. 19 includes aplurality of linkages forming a tubular configuration and a plurality ofstaple ends extending from the linkages. FIGS. 20-22 illustrate how thestaple ends 116 of the staple device 114 are positioned in the end ofthe graft vessel 32 and are inserted through the incision 118 in thetarget vessel and bent over by contact with the staple bending features108 of the anvil. As shown in FIG. 22, the opposite ends 120 of thestaple device 114 are folded over to complete the anastomosis. FIG. 23illustrates a completed anastomosis performed according to the stepsillustrated in FIGS. 19-22.

FIGS. 24-27 illustrate an alternate example of an anvil arm 14 d havinga cutting wire 124 for forming the incision in the wall of the targetvessel 30. The cutting wire 124 may be used to form an incision before,during or after performing an end-to-side anastomosis procedure.Referring particularly to FIGS. 26-27, for forming the incision afterthe anastomosis procedure, a clamp 126 is used to trap the tissue at theanastomosis site between the clamp 126 and the anvil arm 14 d prior toperforming the incision. The incision is spaced apart from the entrypoint of the anvil arm 14 d into the target vessel, creating a tissuebridge between the incision made in the wall of the target vessel andthe entry point of the anvil arm 14 d into the target vessel. A portionof the contact between the anastomosed graft vessel and target vesselextends across the tissue bridge, such that the incision is locatedwithin the closed area defined by the contact between the perimeter ofthe end of the graft vessel and the wall of the target vessel.

FIG. 28 shows a system 140 for controlling a tissue site and performinganastomosis. For purposes of clarity, the staple holder and staples havebeen omitted from FIG. 28. The system 140 includes an anvil arm 142, acutter 144, and a graft vessel holder 146 all mounted on a handle 148.The anvil arm 142 is mounted on the handle 148 and connected to a firstactuator 150 that allows the anvil to be moved downward against the biasof a spring inside the handle. The cutter 144 may be spring biased orfixed and is positioned on the handle 148 directly above the anvil arm142. The graft vessel holder 146 includes two fixed arms 152 and twomovable arms 154. The two movable arms 154 are connected to a secondactuator 156 on the handle 148. Depression of the second actuator 156against the bias of a spring within the handle causes the movable arms154 to be moved downward away from the fixed arms to receive portions ofa graft vessel between the movable and fixed arms.

The operation of the system 140 of FIG. 28 is shown in the crosssectional views of FIGS. 29-31. As shown in FIG. 29, an end of a graftvessel 32 is split so that each half of the graft vessel 32 can be heldbetween a fixed arm 152 and a movable arm 154. In order to load thegraft vessel 32 into the system 140, the first actuator 150 and thesecond actuator 156 are depressed to move the anvil arm 142 and themovable arms 154 downward. The split graft vessel 32 is then insertedbetween the fixed and movable arms 152, 154 and the second actuator 156is released to trap the ends of the graft vessel 32, as shown in FIG.30. The anvil arm 142 is then inserted into the target vessel 30 in thesame or similar manner as described above.

Once the anvil has been inserted in the target vessel 30 as shown inFIG. 30, the first actuator 150 is released to allow the anvil to moveupward to tent the wall of the target vessel. FIG. 31 illustrates thetented target vessel 30 positioned adjacent the split and trapped graftvessel 32 in a position for performing anastomosis. The staple holders38 are then advanced in the direction of the arrows D toward oppositesides of the anvil to staple the graft vessel and target vesseltogether. The staple holders 38 may hold a staple strip with anexpandable backbone as shown in FIGS. 10A and 10B, or may instead oradditionally hold different types of staples not connected to abackbone. The staple holders 38 may be provided with movable pins whichallow the spacing between the staples to be adjusted depending on a sizeof the graft vessel used. Once the staples have been placed, the anvilarm 142 is removed and the cutter 144 makes an incision in the targetvessel before or during removal of the anvil.

As described above, staple bending features are provided on the anviland staples are provided at an exterior of the tissue. Alternately, thestaples and/or staple holding strips may be positioned on the anvil andan exterior member with staple bending features may be moved toward theanvil to bend the ends of the staples and secure the graft and targetvessels together.

FIGS. 32-33 illustrate the use of an alternate anvil 130 for controllingthe tissue at an anastomosis site. The anvil 130 includes a longitudinalopening 132 extending through the anvil 130 for application of aplurality of conventional sutures at the anastomosis site. According tothis method, the anvil 130 is inserted into the target vessel 30 andpulled against the interior wall of the target vessel 30, tenting thetarget vessel as shown in FIG. 33. Sutures 134 are then passed throughthe opening 132 in the anvil 130 and through the tissue of the targetvessel wall on opposite sides of the anvil 130. Once the sutures 134 areplaced as shown in FIG. 33, an incision is made in the target vesselalong a center of the anvil 130. A center portion of each of the sutures34 is then pulled out through the incision in the target vessel and cutso that an even row of sutures is provided along each of the sides ofthe incision. This system eliminates the tedious procedure of placingeach individual suture very close to the edge of the incision in thevery thin and flexible target vessel wall. Each of the sutures 134 isconnected to a graft vessel in a conventional manner completing theanastomosis. The anvil as shown in FIGS. 32-33 allows quick and easyplacement of a plurality of sutures in a very even manner close to theedge of the incision. For example, the sutures of a conventionalanastomosis are generally within about one millimeter of the edge of theincision and are advantageously within 0.5 millimeters of the edge ofthe incision.

In an alternate embodiment, the cutter 200 does not include one or moreprojections 208. Instead, the cutter 200 includes or is connecteddirectly or indirectly to an energy source (not shown), which is used tocreate an opening in the wall of the target vessel. For example, anemitter of laser or RF energy, or another type of energy, may beconnected to the cutter 200 and to the energy source. As the cutter 200translates along the anvil arm 14, it translates the emitter of laser orRF energy relative to the wall of the target vessel. The emitter oflaser or RF energy is selectively actuated to transmit energy into thewall of the target vessel during translation of the cutter 200, therebycreating an opening therein. The energy source may transmit a first typeof energy to the emitter or other mechanism, which is converted by theemitter into a second type of energy delivered into the wall of thetarget vessel. Alternately, the cutter 200 may include a projection 208and additionally be connected to an energy source that is selectivelyactuated in order to assist in creating an opening in the wall of thetarget vessel.

In an alternate embodiment, the cutter 200 does not translate throughthe anvil arm 14. Instead, the cutter 200 is spatially removed from theanvil arm 14, and creates an opening in the wall of the target vesselbefore or after the anvil arm 14 is inserted into the target vessel. Inone example of such an embodiment, the anvil arm 14 is inserted into ahole in the wall of the target vessel and the staple holder 38 deploysstaples or other connectors to connect the graft vessel to the targetvessel, as described above. The anvil arm 14 is removed, and anindependent cutter 200 is then introduced through the hole in the wallof the target vessel. The cutter 200 may be configured as describedabove, including a projection 208 extending therefrom, or may beconfigured differently. The cutter 200 is manipulated relative to theconnection between the target vessel and the graft vessel to create anopening at the junction therebetween. That is, registration ismaintained between the cutter 200 and the junction between the end ofthe graft vessel and the wall of the target vessel. In order to positionand manipulate the cutter 200 to create an opening at the location ofthe junction between the target vessel and the graft vessel, an imagingdevice (not shown) or other device may be connected to the cutter 200 orutilized in conjunction with the cutter 200. For example, a standardintravascular ultrasound unit may be connected to or used in conjunctionwith the cutter 200. The intravascular ultrasound unit is connected to adisplay device (not shown) visible to the operator. The operatorcontrols the intravascular ultrasound unit to visualize the interior ofthe target vessel and the surrounding area, thereby locating thejunction between the target vessel and the graft vessel and allowing thecutter 200 to be controlled to incise an opening in the wall of thetarget vessel within the closed area on the wall of the target vesseldefined by the perimeter of the end of the graft vessel, therebyallowing blood to flow through the opening into the target vessel. Adifferent visualization device or devices may be inserted into orpositioned outside of the target vessel to locate the junction with thegraft vessel. The cutter 200 and any visualization device present in thelumen of the target vessel are then removed from the lumen of the targetvessel, and the opening in the wall of the target vessel through whichthey were removed is sealed.

In another example of such an embodiment, the anvil arm 14 is insertedinto a hole in the wall of the target vessel and the staple holder 38deploys staples or other connectors to connect the graft vessel to thetarget vessel, as described above. The anvil arm 14 is removed, and thehole in the wall of the target vessel is removed. A cannula (not shown)is inserted into the lumen of the graft vessel through the free end ofthe graft vessel, and a stylet (not shown) is inserted through the lumenof the cannula. The cannula and the stylet are surgical instruments thatare well known in the art. The stylet has a distal end configured topenetrate the wall of the target vessel. Thus, a sharp point, blade, orother penetrating member may be formed into or connected to the distalend of the stylet. The cannula may be inserted into the lumen of thegraft vessel such that its distal end contacts the outer wall of thetarget vessel. After the stylet has been inserted into the cannula, aforce is exerted on the stylet to cause its distal end to penetrate thewall of the target vessel. Consequently, an opening is created betweenthe graft vessel and the target vessel within the circumference of theend of the graft vessel. The cannula and stylet are then removed fromthe lumen of the graft vessel through its free end.

In another example of such an embodiment, the anvil arm 14 is insertedinto a hole in the wall of the target vessel and the staple holder 38deploys staples or other connectors to connect the graft vessel to thetarget vessel, as described above. The anvil arm 14 is removed, and thehole in the wall of the target vessel is closed. An independent cutter200 is then introduced through the wall of the graft vessel. The cutter200 itself may create an opening in the wall of the graft vessel throughwhich it can enter, or a separate implement may be used to create anopening in the wall of the graft vessel. The cutter 200 may beconfigured as described above, including a projection 208 extendingtherefrom, or may be configured differently. For example, the cutter 200may be J-shaped or L-shaped to facilitate creation of the openingbetween the graft vessel and the target vessel through the wall of thegraft vessel. The cutter 200 is manipulated relative to the connectionbetween the target vessel and the graft vessel to create an opening inthe wall of the target vessel at the junction therebetween. That is,registration is maintained between the cutter 200 and the junctionbetween the end of the graft vessel and the wall of the target vessel.The cutter 200 is then removed through the wall of the graft vessel, andthe opening in the wall of the graft vessel is sealed.

While the invention has been described in detail, it will be apparent toone skilled in the art that various changes and modifications can bemade and equivalents employed, without departing from the presentinvention. It is to be understood that the invention is not limited tothe details of construction, the arrangements of components, and/or thesteps of performing anastomosis set forth in the above description orillustrated in the drawings. Therefore, the invention is not to berestricted or limited except in accordance with the following claims andtheir legal equivalents.

1. A surgical tool for performing anastomosis between a graft vessel anda target vessel, comprising: an anvil; a cutting element connected tosaid anvil; and an energy source connected to said cutting element,wherein said energy source is configured to deliver energy to saidcutting element.
 2. The surgical tool of claim 1, wherein said cuttingelement is configured to vibrate upon delivery of energy thereto.
 3. Thesurgical tool of claim 1, wherein said cutting element further comprisesan emitter connected to said energy source.
 4. The surgical tool ofclaim 3, wherein said emitter is configured to emit laser energy upondelivery of energy thereto.
 5. The surgical tool of claim 3, whereinsaid emitter is configured to emit radio frequency energy upon deliveryof energy thereto.
 6. The surgical tool of claim 1, wherein said cuttingelement is movably connected to said anvil.
 7. The surgical tool ofclaim 6, wherein said anvil includes a channel defined therein, whereinsaid cutting element is movable within and along said channel.
 8. Thesurgical tool of claim 7, wherein said cutting element includes at leastone projection extending generally upward.
 9. The surgical tool of claim8, wherein at least one said projection is movable upward, then along,then downward relative to said channel.
 10. A method for performinganastomosis between a graft vessel and a target vessel, each vesselhaving a lumen therein, comprising: placing an end of the graft vesselagainst a side of the target vessel; creating an opening in the wall ofthe target vessel at a first location; inserting an anvil through theopening from outside the wall of the target vessel into the lumen of thetarget vessel; creating an incision in the wall of the target vessel,the incision spaced apart from the first location; and connecting thegraft vessel to the target vessel.
 11. The method of claim 10, whereinsaid creating an incision is performed by translating a cutting elementrelative to said anvil.
 12. The method of claim 11, wherein said placingan end of the graft vessel against a side of the target vessel defines aclosed area on the side of the target vessel, and said incising isperformed by controlling said cutting element to position said incisionentirely within the closed area.
 13. The method of claim 12, whereinsaid controlling is performed by biasing said cutting element upward andproviding at least one control element on the upper surface of saidcutting element.
 14. The method of claim 12, wherein said controlling isperformed by biasing said cutting element downward and providing atleast one control element on the lower surface of said cutting element.15. The method of claim 11, wherein said anvil includes a channeldefined therein, and wherein at least part of said translating comprisestranslating at least part of said cutting element within and along saidchannel.
 16. The method of claim 15, wherein said cutting elementincludes at least one projection extending generally upward; furthercomprises moving said projection to a position completely within saidchannel after said creating an incision.
 17. The method of claim 10,wherein said creating an incision is performed outward from the lumen ofthe target vessel through the wall of the target vessel.
 18. The methodof claim 10, wherein said creating an incision is performed bydelivering energy from said cutting element to the wall of the targetvessel.
 19. The method of claim 18, wherein said delivering energycomprises delivering ultrasonic energy.
 20. The method of claim 18,wherein said delivering energy comprises delivering laser energy. 21.The method of claim 18, wherein said delivering energy comprisesdelivering radio frequency energy.